Grinding machine



May 4 1926. 1583.351

..|.v N. HEALD |.r Al.

alumnus lucarne Filed July 14, 1922 2 Shout-Shoot 1 3o May 4,1926. 1,583,351

J. N. HEALD Er AL .GRINDLNG MACHINE Filed July 14,; 2 Sheetg-Sheet 2 chusetts,

Patented May 4, 1926.

" UNITED f STATES. P'ATYENT oFFicE.

JAMES N. REALI) AND ALBERT TURNER, 0E WORCESTER, MASSACHUSETTS, AS-

SIGNoRs To' yTHE REALD MACHINE A CORPORATION or MASSACHUSETTS.

COMPANY, 0F WORCESTER, vIMIASSA.CHUASIIEI'II'PJJS,

GRINDING MACHINE. a'

applicati@ mea my 14, 1922. serial No. 574,940.-

To all whom z'zmay Gomera:

Be it known thatwe, JAMES N. HEALD -and ALBERT TURNER, lcitizens of-.the United States, residing at Worcester, in the county of Worcester and Commonwealth of Massahave invented certain new and u 'seiul Improvements in a Grinding Machine, of which the following, together with 4the accompanying drawings, iis a specification. a

'The vpresent invention relates to grind ing machines. The invention resides in the novel combination and arrangement of parts hereinafter fully described, of especial util.- ity in the constructionv and operation Aof a grinding machine adapted to operate on cy- Vries the usual lindrical or similar surfaces In the accompanying drawings, Fig. l is a View in side elevation of such a grinding machine, according to the pres-v ent invention.

Fig. 2 is an end view of said machine. Fig. 3 'is atop plan view. Fig. 4 is an enlarged detail sectional view of the head stoel; of the machine. Fig. 5sis a schematic view, partly in section, of certain fluid pressure devices used for reciprocating the work. Fig. 6 is a detail view of valve member.

Fig. 7 is a detail view of the valve cap or closure.

4 Fig. 8 is a transverse sectional view of the fluid pressure control and reversing mechanism.' v

Like reference characters refer to like parts in the dierent figures.

The improvements' forming the subject matter `of the present invention are here shown in connection with. a plain grinding machine ofthe usual construction, embodying a suitable frame or'base 1 which carwheel slide 2, the latter being transversely movable in ways 3, 3,' pro-r vided by the machine frame. The 'slide 2 has journalled therein the spindle of. a grinding Vwheel 4, the latter being driven high speed by any suitable. means, such as a belt 5 which connects' the wheel p ulley 6 with a driving pulley 7 The driving pulley -7 is mounted on a shaft 8, preferably journalled on the lower'rear side of the base the oscillating 1 and driven either from a motor, not

' shown, or from suitable countershafting, hkewise not shown; in any event, the ar rangement is such that the machine is self? -contained as. regards the drive of the grind- 4ing wheel 4, and the lpull on the wheel spindle by the driving devices is ltherefore downward, thus supplementing the weight of the wheel slide 2 in the maintenance for the latter of a firm seat on the framefor base of the machine.' The usual adjustment of the wheel slide 2 in the ways 3, 3 for vthe purpose of positioning the wheel v'for dii'er'ent sizes of workis accomplished by a hand wheel 9 -on the front of the machine,

the latter operating through a screw' or' other means', not'shown, to obtain the cross feed of the wheel '4. The'wheel driving belt 5 is caused to accommodate itself to the various positions of the grinding wheel by a 'sprin pressed tightener pulleyl 10,v which is e ective at all times against the rear side of said belt.

' On th vprovision 1s made for supporting and for rotating the piece of work, which, according to the usual practice, in machinesof this class, is adapted to be given a back 'and' .75: front partof the machine frame forth longitudinal movement in contact with the periphery of 'the grinding wheel 4." To this end, the machine frame provides longitudinal ways 11,` 11 for a Sliding table 12, the movement of which, according to the present invention, is obtained by a liuld pressure controlling and reversing mechanism, of the type, for instance, disclosed in the copending. application :of Drake & Hubbell, l

.Serial No. 528,118, filed January 9, 1922.

As shown in Fig. 5, and as disclosed in detail in the aforesaidcopending application,

the table 12 is suitably connected, asby rod 13, to a double'acting piston 14, contained in a fluid pressure cylinder 15. The piston4 sus` 14 is actuated by the' admission of fluid under ressure to one end or the other of the -c inder 1 5, the luid pressure being for by a pump 16 into a supply pipe 17.

which delivers to a valve device 18, the construction Iof'which, forming no part ofthe;

present invention, in said copending application. The valve device `18 comprises a rotatable reversing valve member 57 (see Figs. 6 and 8) keyed toa shaft 58,9. stationary member 59 having is described and claimedA ports 60l 61 and a valve cap 62 (see Fig. 7) /havmg ports 63 and 64. Port 60 is 1n communicatlon with return pipe 65 whereas port 61 is in communication with supply pipe 17. Port 63 is in communication with pipe19 and port 64 with pipe 20. The reation of members 60, 57 and 62 is clearly shown in the sectional view Fig. 8, and assuming that valvemember 57 -is in the relative position with regard to axial displacement indicated by Figs. 5 and 6, in other words, by projecting valve member 57 of Fig.v 6 onto stationary member 60 of Fig. 5, the controls are then in the neutral position. Valve 'member 57 has three passes, 66, 67 and 68. Pass 66 is always in communication with port 61 and so receives, at all times, the-Huid entering at port 6l. ln the above described neutral position pass 66 is also in communication with both ports 63 and 64- and at the same time passes 67 and 68 communicatewith port 60 and also with ports 63 and 64. Inthis neutral position, the fluid. will be shunted. from pipe 17 through pass 66 to ports '63 and 64 through passes 67 and 68 to port 60 thence back by return pipe 65. At'the same time both pipes 19 and 20 are connected throughfports 63 and 64 to the freely moving fluid, so that the fluid in cylinder 15 will not be constrained and the table 12y may therefore be moved by hand.

A lever 21 is also keyed to shaft 58, the

.upper end ofkthis lever being fitted with a knob or handle, or the like. Assuming now that the lever 21 is moved to the iposition shown in Fig. 1, the valve member 57 will be rotated in a clockwise direction, thus breaking the connection between pass 67 and port 63 and also breaking the connection between pass 66 and port 64. lIt will be obvious then that the only -cutlet from port 61 for the fluid will be by way of pass 66 to port 63 and pipe 19, which will cause the piston 14 in cylindery 15 to move to vthe right carrying the rod 13 and table 12. This 4will force iiuidat the right of piston 14 out ofy cylinder 15 through pipe 20 entering port 64 whereA it is constrained to pass through pass 68 to port 60 and so back-by pipe 65.' It will be obvious,

- without further description, that Ymovement v wise direction,

lof handle 21l to the left andconsequent ro.

tation of valve member 57 in a6\ 1nterclockv causes fluid to enter cylinder v 15 by way of pipe 20 and leave cylinderv 15 by way of pi e 19|,because of the symmetry of members 5 59 and 62.

As described, thev reversing valve device '18 is operable, as shown in Figs. 1 and 8` herein, by the direction controllever 21, the latter having a. disengageable pin 469,v

normally located in a slot 70 of a rocking member 22 whose upper end projects into the path of a pair of adjustable dogs 23 then,

and 24 carried by the table 12.4 These sto or dogs engage'the member 22 alternate y,

whereby to reverse the `direction of travel of the table 12 at each engagement; their longitudinal adjustment determines the throw, or length" of table travel, for any .73. The end of plunger 72 is V shaped a stationaryand operates in connectionl with cam member 74, whereby to. snap member 22 quickly to the right or left after it crosses the central or vertical osition.

Mounted on the reciprocating table 12 are the usual work supporting devices, here shown as a head stock 25 anda ltail lstock 26,- the same providing suitable centers 27, 27 for the support between them of the work. Thev head stock 25 and the tail stock 26 are both directly supported for longitudinal adjustment in suitable ways 28, provided by a memberv 29, the latter adapted' 'to swivel bodily on thetable 12 in order to vary the angularity of the axis of the work, in the' v head stock and .adapted to im art rotation by thexworm gearing 34 to a riving late 35, coaxial withthecenters 27, 27 an en' gageable with the work in the usual manner.

VOn the front of the machine, adjacent to thedirection control lever 21, and in convenient reach of the operator is a pivoted lever 36'lwhich cooperates with start and stop buttons 37,' 38 of a switch device 39 for motor 30. In the position of the parts shown in Fig. 2, wherein the lever 36 has been .drawn outwardly, the starting button 37 is engaged,

thus causing the motor 30 to impart rotation'to the work at a speed which is determined bythe position of the control lever 40 of a speed adjusting device 41 inthe circuit of motor30. In this position of lever 36, a valve 42 in the Huid pressure supply pipev 17 leading to valve 18 is lieldopen by allnk connection 43 with said lever 36. Also, by means of a link connection 44, afvalve 45' in water tion, as shown in Fig. 2, thus insuring a supply of water for the When ythe lever 36 is grinding operation.' thrown-inwardly to en- 4 pipe 46 is moved into open posii M' 53 `farine/C1''respectively' on thetable'dogs 23 gaget'he button 38 for stopping the motor 30, the valves 42 and 45 are closed by their respective links 43 and 44; this shuts off the pressure uid, thus stopping the movement of table 12, and `at the same time prevents wastage of-water afterV the discontinuance of grinding.

ods when the wheel is being dressed, 1s not subject to rotation. However, this intermediate position of the lever 36 is accompanied by a partial opening of both the valves 42 and 45, through their respective link connections 43 and water for the wheel during the dressing op- 44; this insures a supply of eration, and also, a throttled-down'reciprocation" ofthe table 12 to carry the dresser 47 back and-forth in contact with the periphery of the wheel. It is to'be noted that this last named result is obtained, through the medium of valve 42, without in any .way disturbk ing the predetermined setting of speed c'ontrol-valve 48, associated with the reversing valve device 18 and adjustable bfy hand, as described in the aforesaid oopending appli-V cation of Drake 8aI Hubbell, to control -the speed at which the table 12 is moved back and forth during any given grinding operav tion. As a result of this, after the wheel has been dressed, the grindin operation can be resumed at the same spee previously determined upon, ment of lever 36 into contact with starting button 37 causes valve 42 to 'move to its wide-open position.- I

In -the use of the machine for grinding vby 4straight inward cuts, involving no reciprocation of the work in contact with the wheel, it is necessary only to shut off the valve 48 completely, thus discontinuing the fluid pressure supply. Thereupon', the movement of lever 36 to starting position insures the desired supply of water for the grinding opf eration and also insures the desired rotation of the work,-in thel absence, however, of any table. travel whatsoever.

As shownmost clearly'in Fig. 5, the inventiolr'aifords an automatic means for decreasing the speed of table travel at eac-h end ofthe Stroker-thus avoiding the shocksincident to reversal when the movement of the table is at a relatively high speed. For

this purpose is provided .a lever 49, pivoted at 50 to the fixed framework, and carry-ing on its'free end, adjacent to the rocking member-22,' a roller-51. Saidfroller 51 lies in the path of in clined cam surfaces 52 and since the full completed move-4 .v ous reasons,

the work may posed, with relation to the do ging surfaces and 24. The surfaces and53 lareso dis-V l proper, as tol make contact'wit the roller 51,

table, the free end of lever 49 is depressed;

in consequence of which, by' means of link 54, a valve 55 in fluid pressure-'supply pipe 17 is lpartially closed. Thisthrottles the.

fluid pressurel supply, and thus decreases the d speed of travel of the table, as the latter approaches each end of its stroke.

This automatlc speed reduction insuresa smooth reversal of the table, with a-uniform amount of over-run at each end of the stroke, 4' I since thefspeed imparted just before and just after reversal 1s definitely established and remains substantially unaffectedby the lspeed at which the table may be running be tween these limits. This is especially valuable in the grinding of long Work 'of relav tively smallA diameter, where a high table speed is required for eilicient operation and Vwhere the problem of smooth reversal is a` diliicult one. Furthermore, this slowin' up of the table travel is most' desirable w enever a shoulder is to be encountered at' thel end of the surface being ground, since it prevents the withdrawal of the work in the absence of a complete revolution'in contact with the wheel at the point of reversal and thus insures the production of a true diameter at-that point.

As shown in Fig. 1, the machine provides, in additionto the motor starting button 37 (normally operated bythe leverl 36 a starting button 56, which is so connecte in the motor circuit with the speed adjustment device i41 as toy produce, when; held depressed, a very slow rotation of the motor 30. v This allows the driving plate 35 to be brought to any desired tating the disposal in t e machine removal or the diiiicult toV handle. In addition, be made to rotate slowly by button 56 pressed'in,for testing holdingvthis to determine whether or not 1t purposes, or is running true, sprung inthe grinding operation.

We claim, 1. In a4 grindin tion with a table machine, the combinaor supporting the Work,

" of means operable by fluid pressure for reosition, for facilitherefrom, of work that is, or vari orwhether it has been ciprocating said table, an electric motorfcarried-by' said table for rotating the work, and a commoncontrol device for said motor and the Huid pressure supply..

2."In al grinding Imaclnne, the

tion witha `table for supporting' the.l work, of means vope'srable by cip'roca'ting said table, an electric motor carriedby said tablefor rotating vthg work, v

fluid pressure for reles 'combina- L ply-without land a starting and vstopping lever for said` '.motor, adapted to control,

the fluid pressuresupply. v p

3. In a 'grinding machine, the combina- 5 tion with a table for supporting the Work,

of means operable by fluid pressure for reciprocatingsaid table, an electric motor carried by saidtable for. rotating the Work, a grinding Wheel, 'means for .supplying Water to said Wheel and a starting and stopping lever-for saidvmot'or, adaptedto'control, simultaneously, the 'Huid pressure supply and the supplyy of Water to said Wheel'.

4. In a grinding machine, the combination with a table for supporting the Work,

of means operable by fluid pressure for reciprocating said table, an electric motor cary'ried by said table for rotating the Work, and a lever movable into opposite positions simultaneously,

vi20. for respectively starting and stopping said motor and opening and closing the fluid pressure supply, said lever, in an intermediate position,

starting said motor.

` tion .with la table for supportingthe work,

)of means operable by Huid pressure for rcp ciprocatin'g said table, an electric motor carv.rled bypsaid table `for rotating thev Work,. a 'grinding wheel, means for supplying Water to said Wheel and a lever movable into p opposite positions for respectively starting Fand' stopping saidinotor and opening and vclosing adapted to throttle saidsaipf In a grinding machine, the combinathe luidpressure supply andf thev supply of vvater to said wheel', said lever, in an intermediate position, adapted-to throttle said Huid pressure'supply and furnish Water to said wheelwithout starting4 said motor.

6. In a grinding. machine, means operable by fluid `pressure for reciprocating the Work, a control device adjustable to vary the speed ofA said reciprocation, an electric motor, reciprocating 4with thework, for imparting rotation thereto, and la starting and control device, and

throttling reversino-- valve, and means on said table adjacentsai Work, independently said table for dogs to actuate said throttling valve means,

said last tWopmeans being adapted to check the iiow of Huid just pr'or to the lactuation of said reversing valve by said dogs, Whereby a high speed tabl may be reversed with a small but definitely fixed overrun, `said table resuming speed immediately after rversal. ,y i l Dated this 28th day of June, 1922.

JAMES Nl HEALD; ALBERT-TURNER.' 

